Electric telecommunication cable having an axial carrier core

ABSTRACT

Electric telecommunication cable having an axial carrier core, characterized in that the central conductor is bonded to the carrier core. The tape constituting the said conductor may be bimetallic, its internal face being made of a metal which is easy to welded to steel. The carrier cable may also be coated with a film of thermostatic material and the internal face of the tape is coated with a similar film, the two films then being cemented to each other.

United States Patent 11 1 1111 3,914,533 Bendayan 1 Oct. 21, 1975 [54] ELECTRIC TELECOMMUNICATION 3,239,916 3/1966 Love 174/117 A CABLE HAVING AN AXIAL CARRIER 3,309,455 3/1967 Mildner 1 174/131 A CORE 3,681,515 9/1972 Mildner 1 174/110 PM 3,717,719 2/1973 Smith 174/126 CP [75] Inventor: Jacques Bendayan, Lyon, France FOREIGN PATENTS OR APPLICATIONS 1 1 Assigneei Les Cables de Lyon, Lyon, France 198,739 6/1923 United Kingdom 174/117 A [22] Filed: Feb. 25, 1974 Primary Examiner-E. A. Goldberg 1 1 PP N05 1 Attorney, Agent, or FirmSughrue, Rothwell, Mion,

I Zinn & Macpeak [30] Foreign Application Priority Data Feb. 23, 1973 France 73.06595 [57] ABSTRACT Electric telecommunication cable having an axial car- [52] US. Cl 174/126 CP; 174/102 R; 174/107; rier core, characterized in that the central conductor 174/13] R is bonded to the carrier core. The tape constituting [51] Int. Cl. H01B 5/00; H01B 11/00 the a conductor m y be bi-metallic, ts internal face [58] Field of Search... 174/131 A, 126 CP, 1 10 PM, being made ofa metal which is easy to welded to steel. 174/113 C, 117 A, 107, 130, 131 R, 102 R The carrier cable may also be coated with a film of thermostatic material and the internal face of the tape [56] References Cit d is coated with a similar film, the two films then being UNITED STATES PATENTS cemented 10 each other.

2,450,429 10/1948 Henning 174/113 C 2 Claims, 1 Drawing Figure ELECTRIC TELECOMMUNICAT ION CABLE HAVING AN AXIAL CARRIER CORE The invention applies to telecommunication cables and more especially to submarine cables, comprising an axial carrier core made of steel wires on which is applied a good conducting metal tube which constitutes the central conductor of the cable.

According to the known technique, that central conductor consists of a metallic strip which is bent to form a cylinder, the edges of said strip which are situated opposite to each other being welded longitudinally, the tube thus formed being then crimped onto the carrier core.

Such a method has a certain number of disadvantages, to which the cable according to the invention is not subjected.

The cable according to the invention is characterised in that the strip forming the central conductor is a composite metal strip composed, for example, of a lamination of two different metals and is cemented to the carrier core.

The accompanying drawing shows diagrammatically an end of such a cable. In said drawing, 1 designates the carrier core, 2 the layer of cement, 3 the internal composite conductor, 4 the insulation, 5 the external conductor and 6 the external sheath.

Such a cable may be produced by various methods.

It is possible, more particularly, to treat the internal surface of the strip to make easier the cementing thereof to the steel wires of the carrier core.

It is also possible and preferable to use a compound or compound strip whose external face is made of a good conducting metal, and whose internal face is made of a metal which adheres easily to steel. Such a strip is typically made by laminating the two metals without the use of an adhesive. For example, the external face may be made of copper and the internal face may be made of aluminium, which can be welded more easily to steel than copper. A copper-iron or aluminium-iron strip could also be used. The composite strip is bent to fonn a cylinder and its edges are welded longitudinally.

Another method consists in covering the carrier core either as a whole, or each of its wires individually, with a film of thermoplastic material such as polyethylene, and in using as the conductor a metal strip at least whose internal surface is previously coated with a layer of similar material, said layer being welded or cemented to the thermoplastic film of the carrier core.

The cement may be applied to the carrier core by any method; for example, by immersion or impregnation, or even in the form of a compound applied by extrusion.

Another method consists in coating the carrier core with a cement, and applying over said core the metallic conductor, composite or otherwise but preferably composite, said conductor being or not coated with a dielectric or non-dielectric film, specially treated or not, on its internal face, with a view to increasing the efficiency of the cementing.

The cementing method according to the invention makes it possible to use, as the conductor, a folded back strip whose longitudinal edges are simply contiguous without overlapping. But a band folded and overlapping may also be used.

The cement may be, for example, polyisocyanate or an epoxy resin.

I claim:

1. An electric telecommunication cable comprising an axial carrier core made of steel wires on which is welded a central conductor consisting of a composite metal strip having an external face made of copper and an internal face made of a metal which readily adheres to steel, said metal strip being bent to form a cylinder and its edges which are situated opposite to each other being welded longitudinally, the metals of said external and internal faces of said composite metal strip being mechanically and electrically connected.

2. An electric telecommunication cable as recited in claim 1 wherein said internal face of said composite metal strip constituting the central conductor is made of aluminum. 

1. An electric telecommunication cable comprising an axial carrier core made of steel wires on which is welded a central conductor consisting of a composite metal strip having an external face made of copper and an internal face made of a metal which readily adheres to steel, said metal strip being bent to form a cylinder and its edges which are situated opposite to each other being welded longitudinally, the metals of said external and internal faces of said composite metal strip being mechanically and electrically connected.
 2. An electric telecommunication cable as recited in claim 1 wherein said internal face of said composite metal strip constituting the central conductor is made of aluminum. 